1. Field of the Invention
The present invention relates generally to arrangements for forming roof structures of vehicle bodies, and more particularly, is directed to an improvement in roof structure of a vehicle body which includes a foldable canvas top for covering an opening provided on a roof portion of the vehicle body to be openable.
2. Description of the Prior Art
There has been proposed a vehicle body provided with an opening on a roof portion thereof and a foldable canvas top for covering the opening to be openable, so that such open-air feeling as enjoyable with an open car can be obtained, as disclosed in, for example, the specification of British patent No. 1 315 364. A roof structure which is employed in the previously proposed vehicle body having the opening at the roof portion thereof and the foldable canvas top for covering the opening is constituted by way of example as shown in FIGS. 1 to 4.
In the roof structure shown in FIGS. 1 to 4, a roof portion 1 of a vehicle body is provided with an opening 2 and a foldable canvas top 3 for covering the opening 2 to be openable. The foldable canvas top 3 is made of flexible and waterproof sheet material and can be folded in such a manner as shown in FIG. 1 to open the opening 2 and thereby an open-air feeling as enjoyable with the open car can be obtained.
The roof portion 1 of the vehicle body comprises a roof panel 4 on which the opening 2 is formed, as shown in FIG. 2. The roof panel 4 is provided with a front panel portion 5, a rear panel portion 6 and a pair of side panel portions 7 each interconnecting the front and rear panel portions 5 and 6 to form the opening 2 and produced by means of press working in a body.
As shown in FIG. 3, a frame member 8 is engaged with an inner fringe portion of the roof panel 4 to form a loop surrounding the opening 2. This frame member 8 supports the foldable canvas top 3 (omitted to be illustrated in FIG. 3) to be movable for opening and closing the opening 2, as shown in FIG. 4 which is a fragmentary sectional view taken on line IV--IV in FIG. 3.
Referring to FIG. 4, a roof rail member 13 which comprises an outer rail panel 14 and an inner rail panel 15 connected with each other to form a closed cross section is provided at each side of the roof portion 1 to extend in a direction of the length of the vehicle body and to be connected at both end portions thereof to a front pillar and a rear pillar, respectively. The outer rail panel 14 and inner rail panel 15 form a connecting flange portion 16 extending in the direction of the length of the vehicle body at the upper portion of the roof rail member 13 and the side panel portion 7 of the roof panel 4 is fixed on the connecting flange portion 16. A roof molding 17 is put in a hollow between the outer rail panel 14 of the roof rail member 13 and the side panel portion 7 of the roof panel 4 for waterproofing and improving an external appearance of the vehicle body, as shown also in FIG. 3.
The outer fringe of the frame member 8 is superposed on the inner fringe of the side panel portion 7 and fixed thereto by means of a plurality of fasteners 18. The frame member 8 is provided with a rain gutter 19 having drain openings (not shown in the drawings) and a guide rail member 20 having a guide groove 21 and extending in the direction of the length of the vehicle body.
A plurality of sliding members 22 connected to the foldable canvas top 3 are engaged with the guide rail member 20 to be movable along the same. Each of the sliding member 22 comprises a sliding shoe 23, a supporting portion 24 to which the foldable canvas top 3 is attached, and a bracket portion 26 on which a stay 25 for supporting a intermediate portion of the foldable canvas top 3 is mounted. Further, wires 27 are put in wire containing grooves 20a respectively formed on the guide rail member 20 and the foldable canvas top 3 is moved in the direction of the length of the vehicle body when the wires are caused to run in the wire containing grooves 20a by a wire driver (not shown in the drawings). For waterproofing and soundproofing, sealing members 28, 29 and 32 are attached to the frame member 8, and in addition, another sealing member 31 is provided between the outer rail panel 14 of the roof rail member 13 and a door sash 30.
With such a structural arrangement, the foldable canvas top 3 which is provided for covering the opening 2 surrounded by the frame member 8 is moved by means of driving the wires 27 to a rear end of the roof portion 1 to be folded as shown in FIG. 1, so as to open the opening 2 and thereby provide an open-air feeling.
However, in the roof structure thus proposed previously, the opening 2 is fundamentally formed on the roof panel 4 by means of punching and therefore apt to be provided with a relatively small size, especially, in the direction of the width of the vehicle body, so that it is difficult to obtain sufficient open-air feeling such as enjoyed with the open car. Further, the roof panel 4 is easily twisted between the front panel portion 5 and rear panel portion 6 during a punching process in which the opening 2 is formed by punching and during an assembly process in which the roof panel 4 is combined with the vehicle body. This results in disadvantages that the productive efficiency of the roof panel 4 is reduced and the roof portion 1 of the vehicle body in which the roof panel 4 is included would not be assembled with accuracy.